Antiallergenic covering for receiving objects contaminated with allergens and/or fine dust absorbed into the lung

ABSTRACT

The allergen-inhibiting encasing for receiving objects contaminated with respirable fine and extremely fine dust, house dust, moulds and allergens, e.g. excretions of house dust mites, together with air, especially bedding and/or upholstery of all kinds, comprising at least a web of woven fabric or a nonwoven and a mechanical closure, such as a zip fastener, in a configuration blocking the passage of allergens and extremely fine particles. The encasing is characterized in that the web includes a fabric which is coated with polyurethane-acrylate copolymer foam and is equipped with increased density, by calendering, up to a degree of filtration of almost 100% for particles smaller than 1 μm. Also, the zip fastener is sealed on the inner face of the encasing by overlapping with a sealing strip comprising at least three plies of fabric.

BACKGROUND OF THE INVENTION

The invention relates to an allergen-inhibiting encasing for receivingobjects contaminated with respirable fine dust and extremely fine dust,house dust, moulds and allergens, e.g. excretions of house dust mites,together with air, especially bedding and/or upholstery of all kinds.The encasing has at least one web of woven fabric or nonwoven and amechanical closure such as a zip fastener, in a configuration blockingthe passage of allergens and extremely fine dust.

With allergen-inhibiting encasings intended to receive theaforementioned objects, the encasings must on the one hand beair-permeable to a limited extent and on the other hand are to preventcontamination of the surrounding air with respirable fine or extremelyfine dust and allergens. It is, inter alia, necessary to clean theencasing in regular intervals. For this reason, such encasings must beprovided with a suitable closure system which is easy to handle,suitable for repeated use and likewise allergen-inhibiting. It must becapable of diminishing the excess pressure, which occasionally occurswithin the encasing upon volume reduction such as that caused by pushingor kneading movements. Preferably, the diminishing of the excesspressure should be gradual enough for the sudden change of pressure bothin the region of the textile web as well as of the closure systems to beuniformly low, so that no respirable fine dust and allergens may beemitted thereby.

It is known to provide an almost air-impermeable encasing for beddingand upholstery with a zip fastener which can, in addition, be sealed bymeans of a pressure-sensitive adhesive tape suitable for multiplerepeated closing. To this end, the constitution of the web material musthave comparatively satisfactory air permeability with simultaneousparticle impermeability to respiratory fine dust in the range of <10 μm(U.S. Pat. No. 5,321,861).

In WO 96/21379 there is described an allergen-inhibiting encasingwherein the upper part of the enclosed space consists of a dense, coatedmaterial, whereas the bottom side consists only of a dense materialwhose air impermeability is greater than that of the zip fastener andthrough which air can emerge more easily than through the zip fastener.Here, too, however, the prerequisite must be met that the fabric of thebottom side has a comparatively high particle imperviousness torespirable fine dust.

In EP 0 600 459 A1 there is described an allergen-inhibiting encasingwith a zip fastener of a polyethylene nonwoven (Tyvek) wherein at leastone overlapping portion of the web in front of and/or behind the zipfastener is intended to provide a reliable seal. To achieve this itwould, however, in any case be necessary for the far-projecting,overlapping web portions to rest planar with the zip fastener to besealed, both against the inner face as well as against the outer face ofthe encasing, which, given the common use of bedding, is frequently notthe case.

A difficulty of all known solutions is that the web material which is tobe used for the allergen-inhibiting encasing must on the one handpossess a comparatively high permeability to air and water vapor and onthe other hand a high degree of impermeability to particles. Theserequirements are contradictory in terms of physics since high airpermeability is inevitably connected with a reduction of the particleimpermeability. Insufficient particle impermeability can lead torespiratory tract symptoms as a result of aerogenic contact withextremely fine dust loaded with allergens of the aforementioned type,and as a result of emerging natural rubber latex products. Here, thetrigger substances are proteins which attach to dust particles and whichto a substantial extent are present in particle sizes smaller than 1 μm.

SUMMARY OF THE INVENTION

It is the object of the present invention to configure anallergen-inhibiting encasing such that a material of a web of theencasing filters out particle sizes of smaller than 1 μm and thusinevitably has a comparatively low air permeability. A closure system ofthe encasing at the same time is configured such that on the one hand itcan be repeatedly operated many times and thus prevents the occurrence,upon ejection of air, of an increased flow rate through the closuresystem, with the result that allergenic dust and extremely fineparticles are not emitted in concentrations above the permissible oracceptable limits, while the encasing nevertheless has a satisfactorywater vapor permeability which markedly improves sleeping comfort. Thisalso prevents the formation of moulds due to accumulation of moisture inthe interior of the encasing.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a cross-sectional view of an allergen-inhibiting encasing ofthe present invention.

DETAILED DESCRIPTION OF THE INVENTION

To achieve the object of the invention in an allergen-inhibitingencasing of the present invention the encasing has a web which includesa fabric which is coated with polyurethane-acrylate copolymer foam andis equipped with increased density, by calendering, yielding a degree offiltration of almost 100% for particles smaller than lAm. A zip fasteneris sealed on an inner face of the encasing by overlapping with a sealingstrip comprising at least three plies of fabric. The fabric of the webpreferably has a high water vapor permeability and has an airpermeability of not greater than 240 liters/m²/min at 196 Pa.

By means of the configuration of the allergen-inhibiting encasingaccording to the present invention it is reliably ensured that uponoccurrence of excess pressure in the encasing there are emitted into thesurrounding air only such amounts of respirable fine dust as are clearlybelow the permissible and acceptable limits for individuals havingallergies.

To this day, only few limits have been defined in the literature ofallergy research. For individuals with highly sensitive house dust miteallergies there is a threshold indication of about 10 ng/m³ of air. Forlatex allergies there is no clearly defined value available. Theimperviousness of the system, however, prevents allergens (proteins ofnatural rubber latex products) attached to fine dust particles smallerthan 10 μm from being emitted from the encasing in impermissibleconcentrations. Due to the fact that the zip fastener is sealed on theinner face of the encasing by overlapping with a sealing stripcomprising at least three layers of fabric, the sealing strip, uponoccurrence of excess pressure between the encasing and the surroundingatmosphere, places itself against the zip fastener in a non-positiveconnection, and forces the air to diffuse through the three layers offabric. Here, too, a degree of filtration of almost 100% for particlessmaller than 1 μm is ensured.

Advantageous embodiments of the zip fastener sealing are provided inwhich it is also possible to equip the encasing with seams havingallergen-inhibiting impermeability.

One use of the encasing according to the invention provides for beddingfor individuals with allergies that is enclosed, and also provides forcovers for latex mattresses that are for protection against latexallergies.

Further details, features and advantages of the invention are evidentfrom the following explanation of an embodiment which is schematicallyillustrated in FIG. 1.

The represented detail of the allergen-inhibiting encasing according tothe invention for receiving objects contaminated with respirable finedust, house dust, moulds and allergens, e.g. excretions of house dustmites, together with air, especially bedding and/or upholstery of allkinds, comprises web portions 4 of woven or nonwoven fabric and amechanical closure in the form of a zip fastener 1, in a configurationwhich blocks the passage of allergens and extremely fine particles. Tothis end, it is provided that the web 4 includes a fabric which iscoated with polyurethane-acrylate copolymer foam and is provided withincreased density, by calendering, up to a degree of filtration ofalmost 100% for particles smaller than 1 μm. The zip fastener 1 issealed on the inner face of the encasing by overlapping 2 with a sealingstrip 3 which comprises at least three plies of fabric 10, 11 and 12. Tothis end, there is provided a configuration having the sealing strip 3wherein the sealing strip 3 starts from a lateral seam 5 between one ofthe zip fastener tapes 7 and a hem 13 of the web of fabric 4. Thelateral seam 5 is crimped over towards the inner face of the encasing,as well as a welting thereof, by a hemming tape 14. The sealing strip 3is connected thereto and is in the form of a tongue 9. The tongue 9 isfolded in the shape of a hairpin, by means of the joint, particle-prooflateral seam 5. The lateral seam 5 preferably has allergen-inhibitingimpermeability. There is provided on the other side of the zip fastener1 a sealing configuration of a further, at least single-layered, sealingstrap 17 connected by means of a joint seam 6. The sealing strap 17 isdisposed such that it overlaps the entire width of the opposite sealingstrip 3. The sealing strap 17 starts from joint seam 6 which is oppositelateral seam 5. The joint seam 6 is between a zipper tape 8 and a hem 15of the web of fabric 4. The hem 15 is crimped over towards the innerface of the encasing and a welting with a hemming tape 16.

It is evident from the above detailed description that when there is adrop in pressure between the inner faces of the encasing correspondingto the direction of arrow 18, the sealing strap 17, in cooperation withthe sealing strip 3, which is configured as a tongue 9, is moved to anabutting position in nonpositive connection with the bottom side of thezip fastener 1. This achieves almost 100% sealing of the zip fastener 1.On the other hand, however, both the sealing strap 17 as well as thetongue 9 are attached underneath the zip fastener 1 such that they in noway impede the opening or closing of the zip fastener 1 when beingoperated from the outside by means of an appropriate closing member (notshown). Since the lateral seam 5, fabric plies 10, 11, hem 13, andhemming tape 14 are united by a joint lateral seam 5, and thecorresponding, opposite elements by the common joint seam 6, theencasing also ensures an uncomplicated manufacture. The presentinvention represents an optimum solution to the task of blocking thepassage of allergens and extremely fine dust.

What is claimed is:
 1. An allergen-inhibiting encasing for objectscontaminated with respirable fine particles and allergens comprising: aweb having an inner face and having portions defining an opening andincluding fabric which is coated with foam having a density such thatthe fabric provides for filtration of particles smaller than 1 μm; aclosure device extending along said opening for opening and closing ofsaid encasing thereby allowing for placement of the object in saidencasing; and a sealing strip overlapping said closure device andconnected to the inner face of the web, said sealing strip comprising atleast three plies of a fabric.
 2. The encasing of claim 1 wherein thefabric of the web has an air permeability of not greater than 240liters/m²/min at 196 Pa.
 3. The encasing of claim 1 wherein the fabricof the web has a high water vapor permeability.
 4. The encasing of claim1 wherein the encasing further comprises a lateral seam havingallergen-inhibiting impermeability and configured such that said sealingstrip and said web are connected to each other along said lateral seam.5. A method for protection against allergies comprising encasing anobject contaminated with respirable fine particles and allergens in theencasing of claim
 1. 6. The method of claim 5 wherein the encasingcomprises a cover for a latex mattress for protection against latexallergies.
 7. An allergen-inhibiting encasing for an object contaminatedwith respirable fine particles and allergens comprising: a web having aninner face and having portions defining an opening and having a hemextending along said opening, said web including a fabric coated withfoam having a density such that it provides for filtration of particlesless than 1 μm; a closure device including a zipper tape connected tosaid web at said hem, said closure device extending along said openingfor opening and closing of said encasing thereby allowing for placementof the object in said encasing; a sealing strip overlapping said closuredevice and connected to the inner face of the web at said hem, saidsealing strip comprising at least three plies of a fabric; a hemmingtape provided over said hem on the inner face of said web, said zippertape, and a side of said sealing strip; and a lateral seam configuredsuch that said hem, said zipper tape, said hemming tape and said sealingstrip are connected with each other along said lateral seam.
 8. Theallergen-inhibiting encasing of claim 7 wherein: the closure devicefurther includes a second zipper tape opposite said lateral seam acrosssaid opening and connected to said web; and said sealing strip includesa sealing strap formed from at least a single layer of material of saidthree plies, said sealing strap being disposed such that said sealingstrap overlaps a remaining portion of said sealing strip and includesanother side of said sealing strip; and said encasing further comprises:a second hem extending along said opening disposed opposite said lateralseam across said opening and connected to said second zipper tape; asecond hemming tape provided over said second hem on the inner face ofsaid web, said second zipper tape, and said another side of said sealingstrip; and a joint seam configured such that said second hem, saidsecond zipper tape, said second hemming tape and said another side ofsaid sealing strap are connected with each other along said joint seam.9. The encasing of claim 7 wherein the fabric of the web has an airpermeability of not greater than 240 liters/m²/min at 196 Pa.
 10. Theencasing of claim 7 wherein the fabric of the web has a high water vaporpermeability.
 11. The encasing of claim 7 wherein the lateral seam hasallergen-inhibiting impermeability.
 12. A method for protection againstallergies comprising encasing an object contaminated with respirablefine particles and allergens in the encasing of claim
 7. 13. The methodof claim 12 wherein the encasing comprises a cover for a latex mattressfor protection against latex allergies.
 14. An allergen-inhibitingencasing for an object contaminated with respirable fine particles andallergens comprising: a web having an inner face and having portionsdefining an opening and having a hem extending along said opening, saidweb including a fabric coated with foam having a density such that itprovides for filtration of particles less than 1 μm; a closure deviceextending along said opening for opening and closing of said encasingthereby allowing for placement of the object in said encasing; a sealingstrip overlapping said closure device and connected to the inner face ofthe web at said hem, said sealing strip comprising at least three pliesof a fabric; and a lateral seam configured such that said hem andsealing strip are connected with each other along said lateral seam. 15.The encasing of claim 14 wherein the fabric of the web has an airpermeability of not greater than 240 liters/m²/min at 196 Pa.
 16. Theencasing of claim 14 wherein the fabric of the web has a high watervapor permeability.
 17. The encasing of claim 14 wherein the lateralseam has allergen-inhibiting impermeability.
 18. A method for protectionagainst allergies comprising encasing an object contaminated withrespirable fine particles and allergens in the encasing of claim
 14. 19.The method of claim 18 wherein the encasing comprises a cover for alatex mattress for protection against latex allergies.
 20. An encasingdevice comprising: an encasement defining an opening; a closure devicefor closing said opening; and an overlapping structure on an inner sideof said encasement having first and second flaps overlapping one anotherand said closure device.
 21. The encasing of claim 20 wherein saidencasement includes a fabric coated with foam having a density such thatit provides for filtration of particles less than 1 μm.
 22. The encasingof claim 20 wherein the encasement is impermeable to allergens.
 23. Amethod for protection against allergies comprising encasing an objectcontaminated with respirable fine particles and allergens in theencasing of claim
 22. 24. The encasing of claim 20 wherein said encasingincludes a fabric having an air permeability of not greater than 240liters/m²/min at 196 Pa.
 25. The encasing of claim 20 wherein at leastone of said first and second flaps is formed of two plies.